Device for indicating admixtures to gases and liquids



July 3, 1928.

K. WOLLIN ET AL DEVICE FOR INDICATING ADMIXTURES TO GASES AND LIQUIDS Filed Dec. 4, 1926 k ws m m r Fm m a z J5 9 fi 4 W b HE; f m e J I, 4!. la 0 f .YYII F Patented July 3, 1928.

UNITED STATES PATENT OFFICE.

KARL WOLLIN, OF BERLIN-GHARLOTTENBURG, AND EDUARD ElMOLCZYK, OF BIESDORF SUD, NEAR BERLIN, GERMANY.

DEVICE FOR INDICATING ADMIXTURES TO GASES AND LIQUIDS.

Application filed December 4-, 1926, Serial No. 152,684, and in Germany June 27, 1925.

The present invention relates to an improved device adapted to indicate admixtures to gases and liquids, the said device being actuated by the total quantity of a definite admixture contained in a gas or liquid. It is based upon the principle of combining chemically or physically the respective admixture (or a certain part there of) with an indicating element, whereby the latter is subjected to a change of volume or density. This change is utilized directly or indirectly for actuating an indicator, an electric switch, a valve or the like. It is also frequently necessary that such indicating ele ment be responsive to changes 01" temperature.

In the drawings:

Fig. 1 shows a filter to which the invention is applied, whereby a frangible element is used. 7

Fig. 2 is a modified term of Fig. 1.

Fig. 3 illustrates a further modification of Fig. 1.

Fig. 4 illustrates a still further modification of Fig. 1.

As in many instances the admixture is of little avail if its degree of concentration should drop below a certain point, the lI1('i1- eating element in these instances mustbe 01': such nature,.that it will react only on the quantity of admixture which will exceed a definite minimum quantity per unit of volume. The indicating element must be so designed that it will suffer such change of structure only after absorbing a definite quantity of the admixture, namely, by crumbling, sintering and so on, winch change will actuate the indicating device. A device of this description thus possesses a definite sensitiveness and a definite capacity. The sensitiveness is given by that minimum of con centration of the admixture, above whose limit the influence upon the indicating ment will only take place; and the capacity is given by that quantity of the substance absorbed that will cause the indicating device to act. Both magnitudes can be varied, the sensitiveness of the indicator by changing the quality and the capacity by changing the quantity of the substance of the indicator. Of course, the indicating element can be so designed and mounted that it will be exposed only to a certain portion of the mixture, as already mentioned.

55 The use of apparatus of the kind referred to may be explained by way of example in connection with breathing filters.

Among others, catalyzers, sensitive to moisture are employed for cleaning the breathing air. If the partial pressure of the aqueous vapor of the air in the breathing circuit is higher than the pressure of aqueous vapor permissible for the particular catalyzer, the latter will absorb moisture to such a degree, that it gradually becomes inoperative. Apparatus employing catalyzers of this kind are now furnished to advantage with devices that will notify the bearer thereof in a suitable manner 01 the catalyzer be coming inoperative, in that said devices will act as soon as the critical quantity of moisture is present, for instance in such a manner that the breathing is opposed by an easily noticeable high resistance.

Hygroscopic substances will constitute the indicating element for indicators of the kind described adapted to be applicable here. Among these, substances are chosen whose pressure of aqueous vapor is almost equal to the critical pressure of the aqueous vapor oi the substance of the catalyzer. Furthermore the substance of the indicating element must be treated in such a manner, that the indicating change or structure will take place upon absorption of such a quantity of ad mixture, at which the mass of the catalyzer will become inoperative, as shown by experience. A mode of execution of such indi cating element, for instance may be as follows:

From a suitably selected hygroscopic substance a small brick is made that is mounted in the filter. Calcium oxide, calcium carbide, and phosphorus pentoxide are examples ol' hygroscopic substances suitable for this purpose. The said brick is adapted to crumble upon absorbing a predetermined quantity of moisture. The release of a compressed spring, for instance, caused by such action can be utilized perhaps for closing a suitable valve or the like. The hygroscopic substance must be chosen in such a manner, that it will absorb the moisture of the air passing through, only when the pressure of vapor of the latter remains above a. pressure that will damage the catalyzer. The size of the brick again must be so chosen, that the latter will crumble up only when the moisture of the breathing air which passed through just renders the catalyzer inoperatil ter i n, ter r u pted tive. Both itaets can be ascertained empirically. r

In the accompanying drawings each of the four-figures is a vertical section ill rating a. different typical and satisfactory 3 )rm ot' the invention. In Fig. l, a designates a portion o'tiaitilter to wliich theinvention applied. In a partition I) there is provided an aperture witlra sharp-edged seat 11 adjacent thereto, to co-operate with the valve 0. On the lower side of said aperture there is provided a suitable support lorthe brick f, above'the partition-is a pertoratedcapor housing-h, provided with a guide for the upper end ot the valve stem 6. A spring 9 presses the valve dowmvardly and keeps the lower end oi the stem e in contact with thebriclc f. When the brick crumbles or disintegrates. the valve will be brought upon its seat d and the passage of air through the in cases where it is desired to providea device actuated by a delinit-c change of tem- .perature, the present inventhmcan beadapted tlor this purpose too. lior controlling operations or as safety-devices. apparatus are oitten required which will react to the presence of a. certain substance and also to definite temperatures or cl'ianges oi ten'iperiv ture. ,Up to the present in both instances ditl'erent apparatus had to be used so that the observer had to pay attention to two (litl'erent signals. The union of both appa- .ratusto one thererore constitutes an additional and. essential technical advantage.

By way of example a device is described hereafter, which will actuate a signal either upon absorbing a detinite amount of moisture from the surrounding air or upon reaching a definite degreeot temperature. Forthat pu1'pose,"for instance, a springloaded pin or die may be used, which engages a sina'll brick, the strength of which is reduced'at a certain content. of moisture of the surrounding air to sucha degree. that it will be crushed by the pressure of the spring, the brick may be made of any suitable hygroscopic material, "for instance calcium oxide, calcium carbide, or phosphorus pt-mtoxide. Furthermore parts or the device as for instance the supports of the bricks or the pressure pin or die, may be made of a suitable and easily fusing metal. (*iVootls metal or the like). The. general arrangement oi parts is the same inllig. 2 as in Fig. 1, but the supports 'i for the-brick f consist o'freadily fusible metal pins. Vv hen the ten'iperature rises to the melting point of these pins, the brick 7 loses its support and thevalve'c is closed by the spring g, thus again interrupting the passage of air.

By a suitable selection of: the metal the de vice maybe designed to react to any desired critical temperature, 'At that temperature the supports will melt and the spring-pressure will close the valve. ltthe pressure pin or die is connected with an electrical con- -tact,-the rupture or displacement of the brick will cause an electrical co tact to-be made actuating a hell or the like. In Fig. 3, the brick is supported upon readily it iible pins 4', and =up0n the, melting of these supports the spring g will move the rod or stem 6 and with it the pivoted hand or pointer K: which co-operates with a scale 8. Of course, a suitable window is provi ded 't'orobserving the scale andpointer. The

a substai'itially rigid normally stationary member exposed to contact with the flu-i d flowing through said passage and constructed ot' a n'iaterial atlected by predetermined torei gn admixtures accompanying such .lilui d, a movable device held statitmary and-inactive as long as said member remains in its initial condition but arranged to be-r'eleased when the condition of said member steered by contact with such foreign admixtures, and a device operated by the movement or? said movable device when the latter is re leased.

'2. A device of the class described, com prising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passageand constructed of a material affected by predetermined changes 'in the condition of said fluid, a movable deviceheld stationary and inactive as long said member remains in its initial condition but arranged to be releasedwhen the condition of said member is altered by changes in the condition of the fluid, anda device operated by the movement of said movable device when the latter is released.

3. A device of the class described, comprising a body having a passage fora fluid, a substantially rigid normally stationary member exposed to contact with the 'fluid flowing through said passageand constructed of a'materi'al affected by predetermined changes in the conditionotsaidufiuid and a valve controlling said passage=and held stationary and inactiveas long as sai'd-mem-' lez) 4. A device of the class described, comprising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passage and constructed of a material affected by predetermined changes in the condition of said fluid, and a movable device held stationary and inactive as long as said member remains in its initial condition but arranged to be released for operative movement when the condition of said member is altered by changes in the condition of the fluid.

5. A device of the class described, comprising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passage and constructed of a material which will lose its cohesion upon exposure to moisture, and a movable device held stationary and inactive as long as said member remains in its initial condition but arranged to be released for opera tive movement when the condition of said member is altered by changes in the moisture condition of the fluid.

6. A device of the class described, comprising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passage and constructed of a material which will lose its cohesion upon exposure to moisture, a fusible sup port for said member, likewise exposed to contact with the fluid flowing through said passage, and a movable device held stati0nary and inactive as long as both said memher and said support remain in their initial condition but arranged to be released for operative movement when the condition of either said member or said support is altered by changes in the condition of the fluid.

7. A device of the class described, comprising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passage and construct cd of a material which will lose its cohesion upon exposure to moisture, a fusible support for said member, likewise exposed to contact with the fluid flowing through said passage, a spring urging said member toward said support, and a movable device held stationary and inactive as long as both said memher and said support remain in their initial condition, but arranged to be released, for operative movement under the influence of said spring, when the condition of either said member or said support is altered by changes in the condition of the fluid.

8. A device of the class described, comprising a body having a passage for a fluid, a substantially rigid normally stationary member exposed to contact with the fluid flowing through said passage and constructed of a material affected by predetermined changes in the condition of said fluid, a movable device and means for pressing it toward said member, said device being held stationary and inactive as long as said mem ber remains in its initial condition, but being released, for operative movement under the influence of said means, when the condition of said member is altered by changes in the condition of the fluid.

In testimony whereof we aflix our signatures.

KARL WOLLIN. EDUARD SMOLCZYK. 

